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1.
The preparations and properties are described of novel anionic and neutral mononuclear biimidazolate (biim), bibenzimidazolate (bibzim), or tetramethylbiimidazolate (tmbiim) manganese(I) and molybdenum(II) complexes of the type [Et4N][Mn(CO)2L2(bibzim)] (L = P(OEt)3); [Et4N][Mo(η5-C5H5)(CO)2-(N)2] ((N)22− = biim2−, bibzim2− tmbiim2−); [Mn(CO)4−nLn{H(N)2}] (n = 1; H(N)2 Hbibzim; L = P(OMe)3, PEt3), (n = 2; H(N)2 = Hbiim, Hbibzim; L = P(OPh)3, P(OMe)3, P(OEt)3, P(OiPr)3; [Mo(η5-C5H5)(CO)2{H(N)2}] (H(NN)2 = Hbiim, Hbibzim, Htmbiim, in which the heterocyclic anions act as bidentate chelate groups. Treatment of the anionic complexes with MeI gives neutral derivatives of general formula [Mn(CO)2L2(Mebibzim)] (L = P(OMe)3, P(OEt)3) and [Mo(η5-C5H5)(CO)2{Me(N)2}] (Me(N)2 = Me-biim, Mebibzim, Metmbiim. Cationic manganese(I) complexes of the type [Mn(CO)4−nLn{H2(N)2}][ClO4 (n = 1; H2 (N)2 = H2bibzim; L = P(Ome)3, PEt3), (n = 2; H2(N)2 = H2biim, H2bibzim; L = P(OPh)3, P(OMe)3, P(OEt)3, P(OiPr)3) have also been obtained by treating the corresponding neutral complexes with HClO4. The structures of the complexes have been elucidated by molecular weight determinations, conductance data, and IR spectroscopy.  相似文献   

2.
The covalent carbamoyl carbonyl compounds Re(CO)5COHN2, cis-M(CO)4(L)CONH2, M(CO)3(L)2CONH2 and M(CO)3(D)CONH2 (M = Mn, Re; L = PPh3, PEt3; D = bipy, phen) are formed by reactions of the cationic complexes [Re(CO)6]+, [M(CO)5L]+, [M(CO)4L2]+ and [M(CO)4D]+ (M = Mn, Re; L = PPh3, PEt3; D = bipy, phen) with liquid NH3 with concomitant deprotonation: [M(CO)6?nLn]+ + 2 NH3 → M(CO)5?nLnCONH2 + NH4+ (n = 0, 1, 2) and [M(CO)4D]+ + 2 NH3 → M(CO)3(D)CONH2 + NH4+ The stability of the above-mentioned carbamoyl carbonyl complexes increases from the penta- to the tetra- to the tri-carbonyl derivatives. In all cases the rhenium compounds are much more stable than the corresponding manganese complexes. Whereas the carbamoyl compound Re(CO)4(PEt3)CONH2 can be isolated by reaction of [Re(CO)5PEt3]+ with NH3, the corresponding manganese complex undergoes Hofmann degradation of amides even at ?70°C to form HMn(CO)4PEt3 and NH4NCO. The IR and some mass and 1H NMR spectra of the new hexacoordinated carbamoyl carbonyl complexes are discussed and the reactions of these compounds with liquid NH3, HCl and CH3OH are described.  相似文献   

3.
The kinetics of the migratory insertion reaction of cis,cis-[(diars)- Fe(CO)2L(Me)]+, (Ia–Ig), (L = C6H11O3P (ETPB), P(OMe)3, PhP(OMe)2, PMe3, PhPMe2 Ph2OMe) or Ph2PMe) in the presence of excess L′ (L′ = P(OMe)3 or i-C3H7NC) in methylene chlorine-d2 to form [(diars)- Fe(CO)LL′(C(O)Me)]+, (IIa–IIg), follow the rate law: Rate = kinsert [(I)]. The first order rate constant, kinsert, depends primarily on steric factors and shows an overall increase of a factor of 270 (at 290 K) as L varies from ETPB (cone angle 101°) to Ph2PMe (cone angle 136°). The pronounced steric acceleration of insertion rate is in accord with a unimolecular rate determining insertion step which requires neither inter- nor intramolecular nucleophilic participation.  相似文献   

4.
The complex mer-trans-[Mn(CO)3{P(OMe)2Ph}2X] (X = Cl, Br) is an intermediate in the conversion of fac-[Mn(CO)3{P(OMe)2,Ph}2,X] into mer- cis-[Mn(CO)2{P(OMe)2Ph}3X] in the presence of P(OMe)2Ph in benzene. No direct route between the latter two complexes could be detected kinetically. The results imply a trans carbonyl disposition as a prerequisite for higher carbonyl substitution in octahedral Mn1 carbonyl complexes.  相似文献   

5.
Reaction of fac-[Mn(CO)3(S2CPR3)(Br)] with [Mo(CO)3(NCMe)3] produces a member of a novel class of heterodinuclear complex [MnMo(CO)6(μ-Br)(μ-S2CPR3)] (R = Cy, iPr), which contains S2CPR3 bridging ligands, acting as an (κ-S,S′) chelate towards Mn, and as an (κ-S,C,S′) pseudoallyl group to Mo, without a direct MoMn bond. One carbonyl group in [MnMo(CO)6(μ-Br)(μ-S2CPR3)] can be easily displaced at room temperature by neutral ligands such as PEt3 and P(OMe)3, affording pentacarbonyl complexes, [MnMo(CO)5(L)(μ-Br)(μ-S2CPR3].  相似文献   

6.
Methyl- or phenylN-carboxamido-complexes of platinum(II) Pt(NHCOR')RL2 (L = PEt3, R = Me, R′ = Me, CH = CH2; L = PEt3, R = Ph, R′ = Me; L = PMe2Ph, R = Ph, R′ = Me, Ph; L = PMePh2, R = Ph, R′ =3, R = Ph, R′ = Me) have been prepared by the reaction of KOH with cationic nitrile complexes [PtR(NCR′)L2]BF4. Thermally unstable hydrido-N-carboxamido-complexes could be detected spectroscopically. IR and NMR (1H, 31P) spectra of some of the complexes indicate the existence of a solvent- and temperature-dependent equilibrium between syn-and anti-isomers arising from restricted rotation about the NC bond of the carboxamido-group. The anti-isomer is favoured by nonpolar solvents and by increasing bulk of L. In the complex [PtH(NCCH CH2)(PEt3)2]BF4, IR and NMR spectra show acrlonitrile to be bound through nitrogen, not through the olefinic CC bond.  相似文献   

7.
The reactions of M2Cl4(PR3)4 derivatives (M  Mo, W and PR3  PEt3, PBu3n) with CO at atmospheric pressure in toluene at 70°C to afford M(CO)3(PR3)2Cl2 and trans-M(CO)4(PR3)2 are reported.  相似文献   

8.
The high‐yielding self‐assembly of three neutral rhenium(I) rectangles, [Re2(CO)6(L)(bpe)]2 ( 1 a , L=2,2′‐biimidazolate (biim); 1 b , L=2,2′‐bisbenzimidazolate (bbim); 1 c , L=2,2′‐bis(4,5‐dimethylimidazolate) (bdmim); bpe=trans‐1,2‐bis(4‐pyridyl)ethylene), under hydrothermal conditions is described. The rectangles were structurally characterized by spectroscopic techniques and further confirmed by single‐crystal X‐ray diffraction. Upon irradiation with a Hg lamp at 365 nm, the bpe ligands of rectangles 1 a and 1 b underwent [2+2] photocycloaddition reactions to produce [{(Re(CO)3)2L}2(4,4′‐tpcb)2] ( 2 a , L=biim; 2 b , L=bbim; 4,4′‐tpcb=1,2,3,4‐tetrakis(4‐pyridyl)cyclobutane) through a single‐crystal‐to‐single‐crystal (SCSC) transformation. However, rectangle 1 c , which contained methyl groups on the 2,2′‐biimidazolate ligand, failed to undergo cycloaddition, even after prolonged irradiation. This result indicates that the light‐induced cycloaddition reaction can be preferentially controlled by the remote regulatory substituents, which are attached onto the same backbone of the rectangle complex. This transformation is the first reported utilization of a remote ancillary regulatory ligand that is covalently attached onto a coordination compound to control the [2+2] cycloaddition reaction.  相似文献   

9.
Mono-cyclopentadienyl complexes CpVX2(PR3)2 and Cp′VX2 (PR3)2 (Cp = η5- C5H5; Cp′ = η5-C5H4Me; R = Me, Et; X = Cl, Br) have been prepared by reaction of VX3(PR3)2 with CpM (M = Na, T1, SnBun3, 1/2 Mg) or Cp′Na. Attempts to prepare analogous complexes with other phosphine ligands, PPh3, PPh2 Me, PPhMe2, Pcy3, DMPE and DPPE failed. Reduction of CpVCl2(PEt3)2 with zinc or aluminium under CO (1 bar) offers a simple method for the preparation of CpV(CO)3(PEt3). The crystal structure of the trimethylphosphine complex CpVCl2(PMe3)2 is reported.  相似文献   

10.
[WBr2(CO4]n reacts with alkynes to give complexes [WBr2CO(RCCR)2]2 (1) (R = R′ = Me, Et, Ph; R = Me, R′ = Ph), which react with nucleophiles L{L = CNBut, PPh3, or P(OMe)3} to give monoalkyne derivatives (WBr2(CO)(RCCR′)L2](2). An intermediate bis-alkyne adduct [WBr2CO(MeCCMe)2(CNBut)] (3) was isolated in the reaction of [WBr2CO(MeCCMe)2]2 with CNBut illustrating that cleavage of the dimer (1) is the first stage in these reactions.  相似文献   

11.
The reaction of [Pt(PEt3)3] with CH2I2 affords trans-[Pt(CH2PEt3)I(PEt3)2]I and is believed to proceed via the α-functionalised alkyl cis-[Pt(CH2I)I(PEt3)2], because similar ylides are obtained from cis- or trans-[PT(CH2X)(PPh3)2X] (XCl, Br, or I) with PR3 (PEt3, PBu3n, PMePh2, PEtPh2, or PPh3); cis-[Pd(CH2I)-I(PPh3)2] does not react with excess PPh3, but with PEt3 yields trans-[Pd(CH2PEt3)I(PPh3)2]I; the X-ray structure of trans-[Pt(CH2PEt3)I(PEt3)2]I (current R = 0.045) shows PtP(1) 2.332(7), PtP(2) 2.341(8), PtC 2.08(2), and PtI 2.666(2) Å, and angles (a) C(1)PtI, P(1), P(2): 176.9(8), 91.6(6), 93.4(6), (b) IPtP(1), P(2): 87.1(2), 88.5(2), and (c) P(1)P(2), 166.8(3), and (d) PtC(1)P(3), 118(1)°.  相似文献   

12.
Reaction of the complexes Ru(CO)2Cl2L [L = 2,2′-bipyridyl (bpy) or 1,10-phenanthroline (phen)] with trifluoromethanesulphonic acid under carefully controlled conditions yields Ru[cis-(CO)2] [cis-(O3SCF3)2] (bidentate complexes. From reactions of the trifluoromethanesulphonates with the appropriate bidentate ligands, the new complexes [cis-Ru(CO)2-L(L′)]2+ (L as above; L′ = 4,4′-dimethyl-2,2′-bipyridyl or 4,4′-diisopropyl-2,2′-bipyridyl) as well as the known [cis-Ru(CO)2L2]2+ and [cis-Ru(CO)2bpy(phen)]2+ have been prepared.  相似文献   

13.
The complexes [MHCl(CO)(PPh3)3] (M = Ru or Os) readily undergo substitution at the site trans to the hydride ligand to afford phosphinite-, phosphonite-, or phosphite-containing products [MHCI(CO)(PPh3)2L] [L = P(OR)Ph2, P(OR)2Ph or P(OR)3 respectively; R = Me or Et]. The ruthenium complexes alone undergo further substitution to afford complex cations [RuH(CO)(PPh3)nL4?n]+ [n = 2, L = P(OMe)3; n = 1, L = P(OR)3; n = 0, L = P(OR)2Ph or P(OR)Ph2] which were isolated and characterised as their tetraphenylborate salts. Synthesis of the cationic complexes [IrHL5][BPh4]2 [L = P(OR)3, R = Me or Et] is also reported. Stereochemical assignments based on NMR data are given, and second order 31P and high field 1H NMR patterns are analysed.  相似文献   

14.
Low temperatùre (−70°C) reaction of (cod)2Rh22 (μ-Cl)2 with two molar equivalents of RLi in diethyl ether gives (cod)2Rh2 (μ-R)2 where R = Me, Me3SiCH2. Even though the bridging alkyls are air and moisture sensitive, they may be stored for prolonged periods at −30°C. The bridging alkyls are fluxional at + 20°C and the NMR spectra are consistent with a dimer of idealized D2h symmetry. Low temperature NMR spectroscopic studies suggest that the dimers have idealized C2v symmetry as found by X-ray studies described earlier. The bridging alkyls readily react with Lewis bases to give monomeric (cod)Rh(R)(L) where R = Me and L = PMe3, PEt3, P(NMe2)3, P(OMe)3, py and R = Me3SiCH2, L = P(OMe)3. The five coordinate, fluxional complex, (cod)RhMe(PMe3)2 also may be isolated. The four coordinate (cod)RhMe(PEt3), slowly reacts with toluene to give (cod)Rh(m-tolyl)(PEt3), (cod)Rh(p-tolyl)(PEt3), and methane and (cod)RhMe(PMe3) slowly reacts with benzene to give (cod)Rh(Ph)(PMe3) and methane.  相似文献   

15.
The complexes trans-MCl2(PMe3)4 (M = Ru, Os) react with CO and P(OMe)3 to give the mono- and disubstituted derivatives trans,mer-MCl2(PMe3)3L (L = CO, P(OMe)3) and all-trans-MCl2(PMe3)2[P(OMe)3]2, respectively. On reaction of trans-RuCl2[P(OMe)3]4 with CO and PMe3, the compounds trans,mer-RuCl2[P(OMe)3]3(CO) and trans,cis,cis-RuCl2(PMe3)2[P(OMe)3]2 are synthesized. The reduction of MCl2(PMe3)2[P(OMe)3]2 with Na/Hg in benzene or toluene via {M(PMe3)2[P(OMe)3]2} as an intermediate leads to subsequent intermolecular addition of the arene and to the aryl(hydrido)metal complexes cis,trans,cis-MH(C6H5)(PMe3)2[P(OMe)3]2 (M = Ru, Os) and MH(C6H4CH3)(PMe3)2[P(OMe)3)2 (M = Os). For M = Ru, in the presence of P(OMe)3, the ruthenium(0) compound Ru(PMe3)2(P(OMe)3]3 is formed. The hydrido(phenyl) complexes react with equimolar amounts of Br2 or I2 by elimination of benzene to produce the dihalogenometal compounds cis,trans,cis-MX2(PMe3)2[P(OMe)3]2. The reaction of trans-RuCl2(PMe3)4 with Na/Hg in the presence of PPh3 leads to the ortho-metallated complex fac-RuH(η2-C6H4PPh2)(PMe3)3, which reacts with CH3I, CS2, COS and HCl to give the compounds mer-RuI(η2-C6H4PPh2)(PMe3)3, fac-Ru(SCHS)(η2-C6H4PPh2)(PMe3)3, fac-Ru(S2CO)(CO)(PMe3)3 and RuCl2(PMe3)3, respectively. The paramagnetic 17-electron complexes [MCl2(PMe3)nL4-n]PF6 are obtained on oxidation of MCl2(PMe3)nL4-n with AgPF6. Their UV spectra exhibit a characteristic CT band. [RuCl2(PMe3)4]PF6 and [OsCl2(PMe3)4]PF6 react with CO and P(OMe)3 by reduction to form the corresponding ruthenium(II) and osmium(II) compounds MCl2(PMe3)nL4-n.  相似文献   

16.
Polypyridyl ruthenium(II) dicarbonyl complexes with an N,O- and/or N,N-donor ligand, [Ru(pic)(CO)2Cl2] (1), [Ru(bpy)(pic)(CO)2]+ (2), [Ru(pic)2(CO)2] (3), and [Ru(bpy)2(CO)2]2+ (4) (pic=2-pyridylcarboxylato, bpy=2,2′-bipyridine) were prepared for comparison of the electron donor ability of these ligands to the ruthenium center. A carbonyl group of [Ru(L1)(L2)(CO)2]n (L1, L2=bpy, pic) successively reacted with one and two equivalents of OH to form [Ru(L1)(L2)(CO)(C(O)OH)]n−1 and [Ru(L1)(L2)(CO)(CO2)]n−2. These three complexes exist as equilbrium mixtures in aqueous solutions and the equilibrium constants were determined potentiometrically. Electrochemical reduction of 2 in CO2-saturated CH3CN–H2O at −1.5 V selectively produced CO.  相似文献   

17.
Novel η1-vinyl complexes of the type Cp(CO)(L)FeC(OMe)C(R)R′ (R = R′ = H, Me; R = H, R′ = Me; L = Me3P, Ph3P) are obtainied via methylation of the acyl complexes Cp(CO)(L)FeC(O)R (R = Me, Et, i-Pr) with MeOSO2F and subsequent deprotonation of the resulting carbene complexes [Cp(CO)(L)FeC(OMe)R]SO3F with the phosphorus ylide Me3PCH2. The same procedure can be applied for the synthesis of the pentamethylcyclopentadienyl derivative C5Me5(CO)(Me3P)FeC(OMe)CH2, while treatment of the hydroxy or siloxy carbene complexes [Cp(CO)(L)FeC(OR)Me]X (R = H, Me3Si; X = SO3CF3) with Me3CH2 results in the transfer of the oxygen bound electrophile to the ylidic carbon. Some remarkable spectroscopic properties of the new complexes are reported.  相似文献   

18.
It has been shown that new mer-tricarbonyls mer-[Mn(CO)3L(tmed)]ClO4, (tmed = N,N,N′,N′-tetramethylethylenediamine, L = P(OMe)3, P(OEt)3, P(O-iPr)3) can be readily obtained from the reaction between fac-Mn(CO)3(tmed)Br, AgClO4, and L at room temperature, whereas at 0°C fac-isomers are produced. The opposite is the case for L = CN-t-Bu; mer-[Mn(CO)3(CN-t-Bu)(tmed)]ClO4 is observed at 0°C, and the fac-isomer is stable at 25°C.  相似文献   

19.
The 31P{1H} nuclear Overhauser effects (NOE's) and 31P-spin-lattice relaxation times (T1) for a series of trans-[PdCl2P2], P ? PEt3, PPr3n, PBu3n, PMe2Ph, PMePh2, P(p-Tol)3, P(cyclohexyl)3 complexes are reported. Both the NOE and T1 values depend upon the choice of solvent. The dipole-dipole mechanism dominates the spin-lattice relaxation of the coordinated phosphorus atom with the T1 values for the PEt3, PPr3n, and P (cyclohexyl)3 complexes decreasing with increasing molecular weight of the phosphine.  相似文献   

20.
Summary The reduction of nickel(II) halides with NaBH4 in ethanol has been studied in the presence of various tertiary phosphines and arsines. Complexes of the type XNiL3 have been isolated in this way when X = Cl, Br, I and L = PPh3, AsPh3, no reaction being observed when L = PEt3, PBu3 and Ph2P(CH2)2PPh2.The reaction of XNiL3 with CO gas at room temperature produces pentacoordinate carbonyl complexes XNi(CO)2L2 when L is triphenylphosphine. The lack of stability prevents the isolation of similar complexes when L is trip henylarsine.Structural data obtained by i.r. spectroscopy and susceptibility measurements as well as chemical behaviour of the new complexes are described.  相似文献   

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